In the past, monitoring of the temperature of a moving mass, such as a flowing stream of molten material, has been plagued with problems. Placing a contact temperature sensing device, such as a thermocouple, into the stream alters the flow of the material and is eroded by the moving corrosive mass. When the moving mass is a solid object, placing a device such as a thermocouple in contact with the moving mass results in rapid abrasive wear.
Attempts have been made to mount radiation pyrometers spaced from the flowing mass and sited onto the approximate center or centerline of the flowing mass. The problems with this technique are; (1) the centerline of the moving mass often moves with respect to the sensor, (2) the peak temperature of the mass is not always coincident with the centerline of the flowing mass, and (3) vibrations from surrounding equipment cause the radiation pyrometer to move such that the pyrometer is not always sited on the centerline. When any one of these conditions occur, the output signal will be effected, even though the peak temperature of the flowing mass may have remaining constant. Furthermore, there is no way of determining whether or not the change in output signal is due to one of the above conditions or due to a change in the peak temperature of the moving mass.
It is desirable to have accurate and fairly continuous information on the peak temperature of a moving mass where the temperature of that moving mass is critical to subsequent processing steps and apparatus so that changes can be made either in the apparatus used to heat the moving mass or to subsequent apparatus to compensate for deviations from the desired temperature. Thus the object of the present invention is to provide a method and a system for monitoring the peak temperature of a moving mass in such a manner that the problems mentioned above are overcome.